A method for assessing the environmental impacts of freshwater consumption was developed. This method considers damages to three areas of protection: human health, ecosystem quality, and resources. The method can be used within most existing life-cycle impact assessment (LCIA) methods. The relative importance of water consumption was analyzed by integrating the method into the Eco-indicator-99 LCIA method. The relative impact of water consumption in LCIA was analyzed with a case study on worldwide cotton production. The importance of regionalized characterization factors for water use was also examined in the case study. In and regions, water consumption may dominate the aggregated life-cycle impacts of cotton-textile production. Therefore, the consideration of water consumption is crucial in life-cycle assessment (LCA) studies that include water-intensive products, such as agricultural goods. A regionalized assessment is necessary, since the impacts of water use vary greatly as a function of location. The presented method is useful for environmental decision-support in the production of water-intensive products as well as for environmentally responsible value-chain management.
The purpose of this work was detailed physicochemical, radiological, and toxicological characterization of the composite sample of water intended for human consumption in the Cameron/Tuba City abandoned uranium mining area before and after a combined electrochemical/advanced oxidation treatment. Toxicological characterization was conducted on human lymphocytes using a battery of bioassays. On the bases of the tested parameters, it could be concluded that water used for drinking from the tested water sources must be strictly forbidden for human and/or animal consumption since it is extremely cytogenotoxic, with high oxidative stress potential. A combined electrochemical treatment and posttreatment with ozone and UV light decreased the level of all physicochemical and radiological parameters below the regulated values. Consequently, the purified sample was neither cytotoxic nor genotoxic, indicating that the presented method could be used for the improvement of water quality from the sites highly contaminated with the mixture of heavy metals and radionuclides.
Lithium-ion technologies show great promise to meet the demands that the transition towards renewable energy sources and the electrification of the transport sector put forward. However, concerns regarding lithium-ion batteries, including limited material resources, high energy consumption during production, and flammable electrolytes, necessitate research on alternative technologies for electrochemical energy storage. Organic materials derived from abundant building blocks and with tunable properties, together with water based electrolytes, could provide safe, inexpensive and sustainable alternatives. In this study, two conducting redox polymers based on poly(3,4-ethylenedioxythiophene) (PEDOT) and a hydroquinone pendant group have been synthesized and characterized in an acidic aqueous electrolyte. The polymers were characterized with regards to kinetics, pH dependence, and mass changes during oxidation and reduction, as well as their conductance. Both polymers show redox matching, i.e. the quinone redox reaction occurs within the potential region where the polymer is conducting, and fast redox conversion that involves proton cycling during pendant group redox conversion. These properties make the presented materials promising candidates as electrode materials for water based all-organic batteries.
This research is focused in the monitoring of sediments in circular sewer pipes with different diameters at a flume facility fed with urban wastewater. For this purpose, sediment physical and chemical characteristics, and sediment mobility were recorded. The Structure from Motion photogrammetric technique was used for the measurement of sediment bed evolution. In addition, sediment properties were determined in order to study the cohesiveness of the bed deposits. In particular, the chemical oxygen demand and the oxygen uptake rate of the sediment samples were analysed after different accumulation periods on the pipe inverts, resulting in a relation between these parameters and the mobility processes of solids.
Adsorption of organic substances on reverse osmosis (RO) membrane surfaces may form an organic film on the membrane, known as organic fouling, and cause flow-rate loss. This problem is mostly unavoidable as no pretreatment method exists for perfect removal of possible foulants, including organic compounds resulting from undesirable bioactivity. Understanding the characteristics of fouling layers is an essential step towards overall improvement of RO membrane operations. In this study, the organic fouling in RO membranes treating the effluent of a secondary treatment from an urban wastewater treatment plant was characterized. Headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry has been used for the first time, to provide valuable information of organic fouling. Different polarity SPME fibers were tested for this purpose. In addition, the characterization of the organic fouling obtained by HS-SPME was compared with the results obtained by extraction using several organic solvents. The results indicated that more compound families can be identified by HS-SPME than by organic solvent extraction. Moreover, complementary organic analyses were done for better understanding of the organic fouling in RO membranes, such as total organic carbon and loss on ignition.
The present work investigates the photocatalytic degradation efficiency of biorecalcitrant macrolide antibiotics in a circulating tubular photoreactor. As target pollutants, spiramycin (SPM) and tylosin (TYL) were considered in this study. The photoreactor leads to the use of an immobilized titanium dioxide on non-woven paper under artificial UV-lamp irradiation. Maximum removal efficiency was achieved at the optimum conditions of natural pH, low pollutant concentration and a 0.35 L min(-1) flow rate. A Langmuir-Hinshelwood model was used to fit experimental results and the model constants were determined. Moreover, the total organic carbon analysis reveals that SPM and TYL mineralization is not complete. In addition, the study of the residence time distribution allowed us to investigate the flow regime of the reactor. Electrical energy consumption for photocatalytic degradation of macrolides using circulating TiO2-coated paper photoreactor was lower compared with some reported photoreactors used for the elimination of pharmaceutic compounds. A repetitive reuse of the immobilized catalyst was also studied in order to check its photoactivity performance.
Through the use of case‐control analyses and quantitative microbial risk assessment (QMRA), relative risks of transmission of cryptosporidiosis have been evaluated (recreational water exposure vs. drinking water consumption) for a Canadian community with higher than national rates of cryptosporidiosis. A QMRA was developed to assess the risk of Cryptosporidium infection through the consumption of municipally treated drinking water. Simulations were based on site‐specific surface water contamination levels and drinking water treatment log 10 reduction capacity for Cryptosporidium . Results suggested that the risk of Cryptosporidium infection via drinking water in the study community, assuming routine operation of the water treatment plant, was negligible (6 infections per 10 13 persons per day—5th percentile: 2 infections per 10 15 persons per day; 95th percentile: 3 infections per 10 12 persons per day). The risk is essentially nonexistent during optimized, routine treatment operations. The study community achieves between 7 and 9 log 10 Cryptosporidium oocyst reduction through routine water treatment processes. Although these results do not preclude the need for constant vigilance by both water treatment and public health professionals in this community, they suggest that the cause of higher rates of cryptosporidiosis are more likely due to recreational water contact, or perhaps direct animal contact. QMRA can be successfully applied at the community level to identify data gaps, rank relative public health risks, and forecast future risk scenarios. It is most useful when performed in a collaborative way with local stakeholders, from beginning to end of the risk analysis paradigm.
The 1990s epidemiological studies by Payment and colleagues suggested that an increase in gastrointestinal illnesses observed in the population consuming tap water from a system meeting all water quality regulations might be associated with distribution system deficiencies. In the current study, the vulnerability of this distribution system to microbial intrusion was assessed by characterizing potential sources of contamination near pipelines and monitoring the frequency and magnitude of negative pressures. Bacterial indicators of fecal contamination were recovered more frequently in the water from flooded air-valve vaults than in the soil or water from pipe trenches. The level of fecal contamination in these various sources was more similar to levels from river water rather than wastewater. Because of its configuration, this distribution system is vulnerable to negative pressures when pressure values out of the treatment plant reach or drop below 172 kPa (25 psi), which occurred nine times during a monitoring period of 17 months. The results from this investigation suggest that this distribution system is vulnerable to contamination by intrusion. Comparison of the frequency of occurrence of negative pressure events and repair rates with data from other distribution systems suggests that the system studied by Payment and colleagues is not atypical.
The aim of this study is to determine the general drinking water consumption pattern in Mysore city, Karnataka, South India with special reference to cold water (without boiling), and to construct a data base for water consumption habits of Mysore people. In developing countries microbial risk assessment studies, water intake values are often adopted from developed countries. However, these values may not be suitable for the risk characterization of human populations from tropical regions of developing countries. Hence, the present study aimed to assess the water consumption pattern among the general population in Mysore city as a first attempt in this region. To compare seasonal variations in water consumption patterns, our study was carried in two major seasons, i.e. in the summer (n = 1,256) and winter (n = 1,230) of 2012-2013. Cold water intake rates were assessed by age, gender and season. The results of this study indicate that the average cold water consumption rate during the summer was 1.12 L/day per person and in the winter season was 0.92 L/day per person. The present survey study is believed to be the first attempt to quantify the intake of cold water consumption in Mysore city, Karnataka, South India.
The environmental impacts of a water re-circulating system for fish farming were studied through the case study of an inland turbot farm located in Brittany (France). Life Cycle Assessment methodology was used to evaluate the potential environmental impact through the following indicators: Eutrophication Potential, Acidification Potential, Global Warming Potential, Net Primary Production Use and Non Renewable Energy Use. Two methods were used to assess the farm's nitrogen, phosphorus and solids emissions: nutrient measurement accounting and nutrient balance modelling. The two methods gave similar results for solids and phosphorus emissions, while for nitrogen the measurement-based approach resulted in half the emissions predicted by the model. The uncertainty regarding the potential gaseous nitrogen emissions led us to assess impacts according to three scenarios, differing with respect to emissions of N , N O and NH . This approach illustrates that the uncertainty concerning nitrogenous emissions to the atmosphere leads to uncertainty with respect to the production system's Eutrophication Potential and its Global Warming Potential. The comparison of our results with similar results for large rainbow trout production in a flow-through system points out the impacts associated with the high level of energy consumption in the studied re-circulating system (i.e. Non Renewable Energy Use, Global Warming potential, Acidification Potential). The nitrogenous gas emissions of re-circulating systems require further studies, in order to precisely identify the substances involved and the technological solutions allowing reduced impacts.